If your devices came with a new iMac, they're already paired with the computer. Just turn them on when you first turn on your Mac. To make sure that your device is turned on, check its power switch. If green is visible, the device is on.

If you bought your devices separately — or if they've become unpaired from your Mac — follow the steps below to pair them.

How to set up earlier Apple wireless devices

Then use a wired mouse or trackpad — or the built-in trackpad if you're using a Mac notebook — and follow these steps to set up your earlier Apple wireless devices (such as the Apple Wireless Keyboard, Magic Mouse, and Magic Trackpad):

Turn on your device.

Wait until your device's LED starts blinking, which means that it's in Discoverable Mode. (If the LED is on but not blinking, your device is already paired with another host. To unpair it, choose Apple menu > System Preferences, then click Bluetooth. Hover the pointer over the device you want to remove, then click the button that appears next to the device's name. Turn the device off, then start again at step 1.)

1. Apple Wireless Keyboard requires the passcode that appears on your Mac. Enter the 8-digit passcode on the keyboard, then press Return. Earlier models of Apple Wireless Mouse or Apple Magic Trackpad will connect automatically or show a dialog. If you see a dialog, click Pair or press Return.